.NET 5 released. So what?

.NET 5 was released a few weeks ago. On the Microsoft website you can find a detailed announcement with all the changes, but the main question for me, as a developer, is so what? What do I have with the release of the fifth dotnet, how can I use it, does it make sense to switch to the new version right now? I will try to answer these questions further.

Performance

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private MemoryStream _stream = new MemoryStream();
private DateTime[] _array = Enumerable.Range(0, 1000).Select(_ => DateTime.UtcNow).ToArray();

[Benchmark]
public Task LargeArray()
{
    _stream.Position = 0;
    return JsonSerializer.SerializeAsync(_stream, _array);
}
      
      

        
        
        
      

    
        
        
        
      
      

        
        
        
      

    
    

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var person = new Person { FirstName = "Mads", LastName = "Nielsen" };
var otherPerson = person with { LastName = "Torgersen" };
      
      

        
        
        
      

    
        
        
        
      
      

        
        
        
      

    
    

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{
    < 3000 => 10.00m - 2.00m,
    >= 3000 and <= 5000 => 10.00m,
    > 5000 => 10.00m + 5.00m
}
      
      

        
        
        
      

    
        
        
        
      
      

        
        
        
      

    
    

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docker pull mcr.microsoft.com/dotnet/core/aspnet:3.1
docker pull mcr.microsoft.com/dotnet/aspnet:5.0
      
      

        
        
        
      

    
        
        
        
      
      

        
        
        
      

    
    

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